The Detroit Lions are 4-0. Matthew Stafford is healthy, fulfilling the potential of a No. 1 overall pick, and leading 20-point comebacks seemingly every week. Calvin Johnson isn't having go-ahead touchdowns overturned by questionable rule interpretations. The defense, led by 2010 first-round pick Ndamukong Suh, is shutting down opponents with timely sacks and interceptions. As far as NFL football goes, these are halcyon days in the Motor City.

Not to rain on the parade, but there is one issue developing on offense that could be worrisome for the team going forward. Namely, according to our metrics, the Lions' passing game -- ranked 11th -- is vastly superior to their running game, which currently ranks 30th. True, it's not as important in today's NFL to be a great running team, but teams still have to be able to run for clock-killing first downs in the waning moments of close games, especially in the playoffs. Furthermore, it doesn't take long for NFL defenses to realize that an offense is one-dimensional, and the results aren't pretty for said offense when defenses do.

To put the Lions' disparity between pass offense and run offense into some kind of historical perspective, we searched our DVOA database for teams between 2002 and 2010 that ended the season with a pass offense ranked at least 19 spots higher than their run offense. The search produced 10 teams, which we've listed for you in the table below, along with their ultimate season results.

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